162 



The Ottawa Naturalist 



[Vol. XXXII. 



20 were seen on Sept. 29 at Lake Francis at the 

 south-east end of Lake Manitoba when it seems 

 that the species enjoys better conditions. Though 

 undoubtedly overshooting has had a powerful in- 

 fluence in the depletion of the grouse of the prairie 

 provinces it was probably not the whole cause. 

 Throughout the provinces of Manitoba, Alberta and 

 British Columbia we heard practically the same 

 report in 1917. A great abundance of grouse of all 

 kinds followed by sudden disappearance. Coin- 

 cident with this were unusual numbers of Goshawks 

 and Horned Owls through the late fall and winter 

 of 1916-17 and the failure of the rabbits of all kinds 

 both locally and throughout the north. The con- 

 nection between all this is obvious. The regularly 

 re-occurring dying of the rabbits through the well 

 known rabbit disease deprived the large raptorial 

 birds of their usual food supply, and they were 

 forced to come into more southern sections and turn 

 their attention to the only food to be found there, 

 the grouse, with the result that the latter were prac- 

 tically cleaned out. The story is remarkably con- 

 sistent wherever we obtained first-hand evidence, 

 and applied as well to the lonely reaches of the Red 

 Deer river valley, the preserved areas of Dominion 

 Parks, where shooters rarely or never penetrated, as 

 to sections adjacent to dense settlement where the 

 sportsmen would be a most important factor. When 

 limited to animal or steam locomotion the radius of 

 action of the shooter is comparatively small and in 

 the vast extent of the western provinces there remain 

 large expanses where the birds can live practically 

 undisturbed. By use of the automobile, however, 

 there is little chance of retaining sanctity for any 

 purely natural reservation. However, it cannot be 

 doubted that this particular and present low ebb in 

 upland game life is due more to natural causes than 

 to man. Caution must be used in advocating the 

 destruction of large hawks for it is only a few 

 winter species that can be unhesitatingly condemned. 

 The summer hawks do little if any damage! and 

 will be discussed under their proper headings. 



86. ^MOURNING DOVE, ZenaiduTa macroura. 



Not uncommon, they were seen in small numbers 

 on every visit and as late as Sept. 28, in 1918. 



87. ''^MARSH HAWK, Circus hudsonius. 



This is the commonest hawk of the locality and 

 it was seldom that one or more were not in sight. 

 They seemed to have well defined beats over which 

 they worked regularly at stated times of the day. 

 There were several nests in the vicinity of our camp, 

 one of which was found, though later broken up by 

 some animal of prey of considerable size, as there 

 was evidence of a severe struggle about the nest. A 



fSee Hawks of ttie Canadian Prairie Provinces, 

 by P. A. Taverner, Mus. Bull. No. 28, Geological 

 Survey, Dept. of Mines, Ottawa, Aug., 1918. 



very pretty sight was witnessed several times. One 

 hawk, usually the male, with a mouse or other prey 

 in its talons approached the nesting marsh calling 

 loudly. It was answered by its mate who rose from 

 the nest and came to the call. They circled and 

 manoeuvred a minute and then, as the female passed 

 beneath her mate, he dropped what he held and she 

 with a quick reach of her talon, caught it in the 

 air and returned to the nest or an adjoining knoll to 

 feed it to the young or to herself. Sometimes several 

 attempts would be made by the two birds to get 

 into the proper relative position, but the upper bird 

 never dropped the prey until he was satisfied that 

 conditions were favorable nor, when he did drop 

 it, did we ever see his mate miss the catch. Marsh 

 Hawks were still common when I returned in the 

 autumn of 1917 and when Young left in early 

 October, 1918. 



88. '^SHARP-SHINNED HAWK, Accipiier Velox. 



In 1917, one bird seen on May 25th and other 

 individuals on various days during the September 

 visit. In 1918, Young noted occasional individuals 

 throughout the summer except from June 2, to 

 Aug. 5. 



89. GOSHAWK, Astur airicapillus. 



Though no Goshawks were seen in 1917, Young 

 noted two on Aug. 21, 1918. We received such 

 detailed accounts of the number of "large gray 

 hawks" that visited the country the winter of 1916- 

 1 7 that there could be little doubt as to the identity. 

 Without question these birds together with Horned 

 and Snowy Owls, were the immediate cause of the 

 scarcity of Prairie Chicken, and Sharp-tailed and 

 Ruffed Grouse. This bird is a brush hunter and 

 doubtless accounted for many Ruffed and Sharp- 

 tailed Grouse in the poplar bluffs by day, while the 

 Horned Owls took many by night that roosted in 

 insufficient cover whilst the Snowy Owl that is 

 largely a diurnal hunter scoured the more open 

 places. The trio made a combination that is dif- 

 ficult for any grouse to escape. As mentioned be- 

 fore, doubtless these birds came from the north in 

 such unusual numbers in search of food on the de- 

 pletion of their usual rabbit supplies. To date, 

 February, 1919, we have received no notification of 

 another flight of these birds. On the contrary all 

 reports point towards an increase of rabbits, and a 

 decrease of destructive raptorial birds in the more 

 settled communities, and we assume that it will be 

 several years before the latter become a serious 

 menace again. 



90. *RED-TAILED HAWK, Buteo borealis. 



Next to the Marsh Hawk this was the hawk most 

 often seen. They were shy, though still not quite as 

 wary as the individuals we are in the habit of meet- 

 ing in the eastern provinces. They nest in some of 



